Trolley-pole base



July 8,' 1930.

F. R. DIPFMAN ET AL TROLLEY POLE BASE Filed June 12,' 1928 2 Sheets-Sheet.

fica. Z.

'I nvenlof PID 2?. ./PPM/m/ Eva/:FU M'Oo E July 8, 1930. F. R, DlPM/:LN ET AL I I v1,770,229

TROLLEY POLE BAS E Filed June 1'2, 192s 2 sheets-sheen '2 F/'ff f/PPMAA/ Attorney Patented July 1930 f ry naar ,nnen a; marmer-inne nnsanni ernennen r/mnsrrntnorrro, Assrenons'rnn cierro Basse centenaire@ Mnnsrfrntn, orare, a oonronarro'n or NEW-JERSEY TROLLEY-Penn nasa applicati@ nieu June 12,

. Uur invention relates to a trolley pole base for use in connection with vehicles deriving their source of power rfrom an overhead trolley Wire. v l v TheV object vof our inventionis to provide a trolley base and the method of niainifactur- I ing' the'samewhich shall be light in Weight vyet strong enough to withstand the Anormal Wear and tear thereon and the abuse to which adevice of this character is'subjected.

' Another object is to provide a base which is quick to respond to the various movements required of it with respectvto the caruponk Which it isinounted due to the relative movementof the car and overhead trolley Wire. n Another object oflour invention is to provide a trolley baseand the method of manufacturing` the saine Vin which the manufacturing' defects usually found in such a device, such as casting craclrs, blow holes, shrinks and draws, are elimin'atedand an increased factor of safety is secured Withouty an increase in Weight or sacrifice of' its other re*- quire'ments. e v A Another object of our invention is lto provide a base and the method of manufacturing the same constructed of loW priced rolled steel or Wire in place fof high'priced castings and in which the various parts are forined'up Aout of the rolled materialand Welded together preferably by the are or oxyacetylene Welding processl 'v By our process ofconstructin@ a trolleyr base, We are able to' talre `a design of standard constructionk made of castinfrs, as is the present practise, and substitute therefor parts made of rolled or forgedniateriallandwvelded together and produce a base which isV of equivalent design and comparatively light in Weight, as? for instance, one type of 'base now on the market and made of castings, We have duplicated and reduced the YWeight by Without sacrilicing` any of the requirenents ofthe base, but improving the operai tion of the base'in many respects.

`',Also', in the particular base just referred to, We have found it possible to reduce the ,tension on the springs for yleldingly maintaining the pole in Yproper'position by 50%;

Thisl means reduced pressure Vagainst the The materi'albf Whichlwe preferto conV` struct our basepossesses more elasticity or resiliency than castings and, therefore, the base tends to absorothe 'shocks more readily through a flying polestriking a span Wire or loverhead obstructlon'sY than a base made of castings. f

Sinc'ethe movingY parts of the base con trolled by the springs are materially reducedv in Weight, the pole responds more readily to though the Vspring pressure tending to niove t'he pole upwardly is materially'reduced andV thisl also tends Vtoreduce;the hammerblovv upon the overheadistructure as thel currentV collect-Orpassesthe varioussupports'7 splicers, etc.. u'sed in Yconst'rusting a trolley, linef The materialof which the'base is conlvariations in the overhead obstructions With which the current collector -foontacts -even structed possesses greater resiliency than one inadeof castings through the fact that rolled iron yand steel are practically free from flaws or defects of a character which would afiet the construction of lour base, but this is not true of abase constructed of castings as such vcastings. are liable to possess many. defects Whichdo not'manifestthemselves until the base has'been in use and subjected to commercial' service. The material of vvhi'ch We construct our base hasfa definite'strenlgth per unit area of rcross-section and such strength 'can be relied upon to be repeated in all ma- 'terial used, but this is. not true2 ofcastings as there are many factor'swhich affect the uniformity and'quality.'

The raw material from Which We fabricate practicallyall parts of, our base can be pur-V chased for practically one-third'the price per pound that malleableikzed iron', or r steel Vcastings can be procured for. We find that a less amount of rolled steel or iron is necessaryfor j factory at the present day has one or more welding outfits in use, therefore we require no special machinery or tools as in the case with a base constructed of castings.

In the drawings accompanying this specification;

Fig. 1 is a top plan view of our invention with some of the parts broken away.

Fig. 2 is a one end view of Fig. 1.

Fig. 3 is a side view in'elevation of Fig. 1.

Fig. 4 is a View in partial' section of Fig. 1Y

on the line 4.-4.

Fig. 5 is a sectional view ot' the turret and pedestal taken on the line 5 5 of Fig. 2.

Fig. 6 is a side view of the extreme outer right hand end of Fig. 1.

Fig. -7 is an end view of Fig. 6.

Fig. S is a plan view ofthe adjustable spring holding device.

Fig. 9 is a side view of the same.

Fig. 10 is an end view ot Figs. 8 and 9.

Fig. 11 is a top plan view of the hinged end of the trolley pole holding portion and the J hold-down device.

Fig. 12 is a section al view of the hinged end of the trolley pole holding device.

In the preferred embodiment of our invention and the process of constructing the same, we employ a base member 1 formed up of rolled sheet steel or iron of proper dimensions and thickness to give the required strength and support, and such plate is provided with through openings 2 to receive bolts for securing the device to the car root. The plate 1 is somewhat doineshaped or concaved as this gives added strength and stiffness and in order to strengthen the plate at the center where the upright pedestal 3 is secured, a washer 4 is provided which is formed up out of sheet iron or steel and which has a periphery welded to the plate 1 as at 5.

' lherever we use the term steel, it may be considered that we apply the term in a broad sense to include also iron. Also, when we speak of the parts being welded, we have in mind that the same is carried out by means of the oxyacetylene llame or by the electricV arc, using either the metallic electrode or the carbon arc or other similar means ol welding and which processes are well known to those skilled inthe art and are used er; ensively in the various arts at the present day.

Ne find that a base plate composed or" the members 1 and 4 has a somewhat elastic property which permits the base to yield somewhat under the variable strains to which it is subjected and by building the base plate up of the part 1 reinforced by the part 4, we save metal as against increasing the thickness of the plate 1 throughout its area.

The pedestal 3 is formed from a piece ot solid rolled or drawn stock and we prefer to 'have a shoulder 6 at the lower end and the pedestal is projected through the opening in the plates 1 and 4 and welded about its periphery to the plate 4.

rIhe pedestal 3 may be constructed from tubing` of proper thickness by rolling and drawing operations to produce the various shapes and dimensions thereon it the quantity required is sutlicient to pay for the tools, but with automatic lathes, which re standard equipment nowadays, pedestal 3 can be constructed quite inexpensively from solid rolled or drawn stock.

The pedestal is formed with a shoulder 8 for supporting the ball or roller bearing 9 and with a reduced portion 10 upon which is mounted the ball or roller bearing 11. rIlhe roller bearings are made with a slightly forced ht upon the pedestal suleient to prevent the races from rotating upon the pedesl. The pedestal is also provided with a further reduced portion 12 which is threaded and drilled to receive the castellated nut 13 and spring cot-ter 14.

Mounted upon the pedestal 3 through the medium of the bearings 9 and 11 is a turret member 15 which due to its very irregular shape and thickness ot parts at various points, we find can be constructed to better advan tage from steel or malleableized iron.

rIhe turret 15 comprises a hollow tubular member having a shoulder 16 supported by the bearing 9. Also, a flange 1? upon which rests the bearing 11. In order to maintain the turret and bearing in position upon the pedestal, I employ a washer or plate 18 of rolled material having an orifice thereon to receive the reduced portion 12 ot' the pedestal and adapted to rest upon the inner race of the bearing 11.

lVhen the describedV parts are assembled the washer 18 presses upon the bearing 11, which in turn is support-ed by the shoulder 17 and the turret 3 and this tends to hold the turret down into position with the shoulder 16 resting upon the bearing 49 and which bearing in turn rests upon the shoulder 8 and is held in that position. The castellatcd nut 13 adjustable with respect to the plate 1S engages the plate 18 and holds it in position, thereby adjusting the Ypressure upon the various parts ydescribed and the 14 maintains the nut 13 in its adjusted position.

Projecting laterally from the same side of the turret 3 are two spaced lugs 19 connected by a transverse flange 2O and having form d alongtheir outerl edge adjacent the top, Aa; hook 21 to `be engaged bythe hol-ding device 22, as .later described. Y The lower ends of the,

1ugs19` are eachl rprovided with a passage therethrough to receive the axle Positioned between the lugs 19, .theilange and shoulder 24 is a body of elastic rubber 25 having! the resiliency, elasticityand toughness of what is `known as car spring rubber. This body ofzrubber 'is so'v tensioned as torequire `considerable pressure to place 1t in position lnorder that it will be retained therein. We find that this Lmaterial is suthereon ydue to a nflying pole and the rebound to the pole' is very slight. Theretorej theV stress upon theother parts'of the base seems to be considerably reduced as against the use of a steelsp'ring. Y j f One exposed face or" the rubber buier 25, as indicated by the'arrow 267 is obliquely disposedv and themovable arm of the base strikes this oblique face in the caseol av 'iiying pole atpractically .right angles thereto. l

Mounted uponthe baseV plate 1 are lugs 27 formed of steel or a non-ferrous metal and welded thereto Tas atv'28. rlhese lugs "are i drilled to receive cable terminals 29`and^heldtothe lugs 27 by means of the cap screws 30. Secured to the turret between the lugs 19 .by means ofthe pin 23 is the arm 31 movable parallel to the base in avertical plane. This arm comprises aV hinge member 32 (see Figs.

vided with a projecting portion 33 to receive a` sleeve 34 and welded together at the point 35. The sleeve has an inner tapering portion 36 at the end remote froml the'hinge 32 to receive theend of a trolley pole in a wedging relation and tending to center the end of the pole within the arm 31. :[tl will be evident that this construction will hold the end of the pole absolutely iirm and centered so long as the pole cannot move longitudinally away from the member 34.

Surrounding the member 34,* which is formed of steeltubing or sheet metal rolled into a tube, isanother` tubularmember 37 which extends over a large portion 38 of the hinge member 32 and is welded thereto at 39. lThe member 37is preferably formed of fseamless steel tubing or pipe stock,` which may be formed up of sheet metal and welded along theseam. The parts 34 and 37 fit each other quite closely as the member34 is intended to reinforce the member 37 yat rthe hinge and as well as to receive and center the trolley pole and Vthereby is secured a stronger as formed of round bar steel.

unionof the members 32 and' 37. `The mem? L ber 32 isprovided with a passage 39 through which passes thejpin 23 and which is held y in place by means" ofv a headless set screw 4() such that the pinrotates. with the hinge member 32,*althou'gh the .set screwniaybeused i in connection with the lugs19 toV engagelthe pin 23 if desired. i

Y Mounted upon the tubular?ar'm'37v are two members 41 formed up outer bar steel with L a portion to viit the tubev 37 and upstanding or projecting portionsk 42 spaced apart and f with a rivet or bolt 43 therethrough heldin placeby the' cotter 44. The members 41 are welded to the tube 37l as indicated at 45.V y n Mounted upon'the rivet 43 is the hold-down device 22' operated at will by thefmotorman to engage' with orbe disengaged from the hook 21 to hold thev pole in a practically horizontal osition or to allowit to ouerate freel f in a vertical plane. j v u The hold-down device 22 comprises a piece of bar steel 46 cut to the shape shown and with the slot 47 therein through which passes the' rivet 43 and welded to th'eppposite end of the bar 46 is a Vtransverse member 48 shown- The welding is indicated at 49. In li'gg 4 the hold-down in a horizontal position while in Fig. 11 it is shown in a released position. Y i f To further holdthe trolley pole-in position rwithin .the tubular member`37, theouter end is cut away as shown at 50v andthere is'welded to the end of the tube 37 as indicated. at 51, a, stationary angle piece 52 having a hole through one flange to receive the bolt 53`and two holes through the other flange tojreceive the bolts 54. rlrhe upright ends of the angle 52 may be cut on the bias as shown'in Fig. 7 irn desired or otherwise shaped. L' Y y Mounted on the bolts 54 is a yoke member 55 formed up out of bar steel and which rests in the space 50 at theend of ythe member 37 and is arranged to securely grasp thetrolley Ypole when in position through the.-med1'um tact withthe` trolley wire in yielding relation theretdythe membe'rf37 is further con- Yno j ico lio

nected to the turret through-the medium 'of the' springs 5G.

Projecting on opposite sides of the turret are arms 57m which areA placed studs 58 'and upon the exposed portions of studs 58 are secured one end ofeach spring 56Y andthe outer spring ends are held in place by means ofthe washers 59 and spring cotter 60. '"Th'e studs 58 are held against removal by the cotters 61.

Adj ustably mounted upon the tubular arm k37 is a yoke shaped member 62 arranged to receive the oneend of each spring 56. The

Teh

member 62 is formed up of angle iron or sheet material bent to an angle and has the en'ds of both the horizontal and upright portions bevelled as shown in Figs. 8 and lO, andv the upright portion is formed with a hole 63 therethrough to receive the bolt 53. lVelded to the horizontal portion, as indicated at 64, is a tubular collar 65 Jformed of pipe, seamless steel tube or it may be of sheet material rolled to that shape, and having a slidingr fit upon thearm 37. lVelded to the horizontal portion are hook members 66 formed up out ot sheet steel with the end hooks 6'? arranged to receive the ends of the springs 56.

With the member 62 in position on the tubular arm 37 and the springs in position, the tension upon the springs be varied at will by means of the nut 68 and locl nut 69. The members 66 are secured to the member 62 by welding as indicated at 70.

In order to properly and e'lliciently conduct the current from the turret l to the pedestal 3, I provide a reciprocating spring held contacter 7l preferably made oit cop` per and having eciently connected 'thereto copper leaves 72 which in tur. are clai. pcd betweenthe members 73 and Zet by means of the cap screws 75. The spring is indicated at 76. This construction permits the turret to rotate about the vertical axis or" the pedestal and shunts a very large portion oi the current away from the ball or roller bearings' directly to the pedestal, thereby preventing pitting of the bearings.

At the lower end of the turret 15 is a grease and dust ring 77 which consists oi a sheet steel washer fitting closely between the turret and pedestal and having a binding sheet upon the turret and secured upon the metal washer is a .length of felt which bears against the pedestal. This construction retains any grease that be within the tur` ret and prevents dust from entering therein. Access to the interior of the turret for the application of grease is secured through the pipe plug 78.

There are` of course, modifications which may be made in the construction and arrangement of the parts herein disclosed, but it is believed we are the rst to construct a trolley base in which parts are fabricated from plates, tubes, rods and the like, and the various elements welded in position, thereby forming a much lighter and less er;- pensive trolley base which through its lightness operates more efficiently, and in which a rubber bumper has been substituted for metal springs which secures advantages not derived from a spring, as already pointed out. The turret member 15 could'on many forms of bases be very simply and easily made entirely of a built-up structure and even in the design shown the same could be fabricated as the other parts, possibly at some added cost and modiiication.

The terms sheet steel and iron are used interchangeably as relating to the same thing.

The terms rolled and drawn as applied to steel or iron are considered as equivalents and in the claims we have used the term structural as referring to the class of material used, such as rolled, drawn or forged steel or iron as distinguished from castings and the term structural dees not apply to any particular shape.

Vle claim l. In a trolley base, the combination with a cast turret member of a fabricated support and a fabricated arm and springs biased to yieldingly hold the arm in an upright position; the support comprising a Ydished plate ot structural steel having an auxiliary plate ot structural steel of less area than the irst plate and welded along its edge to the lirst plate, a hole through the two plates to receive a pedestal member projectingY upward through the hole and welded to one of the plates, the pedestal formed from structural steel and with means thereon to support an anti-friction bearing, a. shoulder within the turret to rest upon the bearing to support the turret and a second shoulder-within the turret upon which is supported a second bearing, both bearings surrounding the Apedestal and su porting the turret in rotatable relation thereto about the aXis of the pedestal member, means formed on the first said plate to secure the base to a car; the pole arm comprising a hinge member formed of structural steel rod and pivotally mounted on the turret and a structural steel tubular member enclosing a portion of the hinge member and welded thereto and a reinforcing` tubular member of structural. steel positioned within the lirst tube and enclosing a portion of the hinge member and welded thereto and the free end of the reinforcing tube having its inner surface tapered outwardly to receive and center the end of the trolley pole in wedging relation, a portion of the free end of the first tubular member being cut away and a clamp device secured thereto by welding and comprising a transverse part et structural steel welded to the tubular member and having bolts therein to support a formed up clamp member to gri the pole and held in gripping relation by the bolts.

2. A trolley base comprising in combination a turret member, a support therefor, a pole arm and springs biased to raise the arm; the support comprising a plurality of parts formed of structural steel and welded together; the turret mounted on the support with anti-friction bearings interposed between the support and the turret; the pole arm pivotally mounted on the turret and comprising a plurality of parts formed up of structural steel and welded in place and arlim be secured to a car and another part compristhe convex Vsur- Y ,3.9 4 spring secured to the holding means to move I ranged-.to clamp the pole inp'lace, secure one end ofthesprings and :adjust thef'tension thereon; :means on the turret-,toy secure the other en d of the springs thereto; and a member to' receive the impact ofthetrolley poleI when it 'leS upward andfyieldinglyarrest-J itsr further upward moi'fement.

A trolley kbase having formed upY Y,

ofstructural'steel and weldedtogether, one part comprising a concavo-convex memberto ing a stem projecting from face of saldmember. j

` 4. In a trolley base, the combination with form anadjustable clamp member to grip the.,

pole in'position 'within the arm and a second structural steel member of a-plurality of parts welded togetherfand mounted on the arm kin longitudinally adjustable relation thereto and having spring holding means; and means to adj-ust the second structural steel member; spring holding means on the turret and a thearm vand pole upward when in a released condition. n v 5. Ina trolley base, theA c ombinationgwith aturret'and'a p'ole arm secured thereto to pivotin a vertical"plane"and springs biased to move thearmqabout its pivotggofa support.

comprising a dished memberformed up of a steel plate cut to size and shape an'dhaving a central hole therein and other holes to secure the member toa car, an auxiliarymember shaped from'a steel plate .and Welded to the first member and having avhole to correspond with the lirst hole, a pedestal mem-ber formedof structural steel Yand projecting through the said holes and welded tothe said plates to form a support for the turret; anti-friction bearings interposed between,l `the pedestal.

Y Vmember and the Vturret'and supported bythe pedestal member and permitting the turret to rotate about the verticale-iris of the ped estal member. f I,

6. In a trolley base, the combinationwith a turret, a pole arm secured thereto to pivot in'a vertical plane and springs biased to move the arm about its pivot of a support comprising a member formed of ysteelplate and are`- inforcing member formed of steel plate and welded to the first member adjacent its center, a hole through the members to receive a pedestal rmember therethrough andV having a shoulder Vto be welded tothe said plates',a shoulder formed on the pedestal member to receive and support an anti-friction bearing mounted on thev shoulder; a second anti-friction bearing on the pedestal; the )turret mounted on the bearings'and arranged to; roT

' tate about thevertical axis ofthe pedestal and means to hold. the

turret in position on the ,pedestaLQ turret mounted thereon; l antilfriet'ion bear-l port, adj ustablegmeans toV hold the turret von thels'upport, a pole arm f ormedup of tubular and structural steel parts'welded together and having a formed up hinge member Aweldbiased to move the arm upward-and afrubber bumper interposed between thepole and turret to receive the upward throwof the 'polei 7.' A-trolley basecompri'sing sripportla ings interposed between the turretand sup edto the tubular partand secured tothef turret to pivot ina vertical plane, springs Y 8. -A trolleyv base comprising awfsupport,` `a g turret mounted thereon, anti-frictionbearf.

ings interposed between theturret and 'Support, a polearm hingedupon `the turret to pivot in a vertical plane, 'springs biased to move the free endof thearmupward and; a i yieldable rubber bumper interposedbetween the arm and one ofthe yaforesaidfelementsto cushion theupward throw of the arm.

9. A- trolley basecomprisinga support, a l

turret rotatablym'ounted on the support 'and carrying a polearm -pivotedto movein a ver# tical plane, `the vpole arm comprising a'steel tubing' welded toa steel hinge member YandA a transverse memberwelded tothe en-d' of the Varm to carry a pole clampand springs l :biased to'move the arm upward."4 Y

1 0. A'pole arm for atrolley'base compris# inga tubular vpole receivingV member of structural steel, a structural steel member atene end t-o forml a hinge, an angularstructural steel member at the' other end weldedtothe tubularrmember in a transverse position and havingrmeans to carry a po'lecla'mp thereon;

a structural member positioned transverse of the tubular membenand Va tubular collar of structural steelwelded tothe transverse member to slide longitudinally upon the tubular receiving member, means welded to the. trans- Vversemember to secure springs thereto/and up of steel and' having a cylindrical outer side surface and proj eoting through the holes and beyondthe surface of one' ofthe plates and having the periphery ofthe pedestal adv jacent one end-'welded to one of the plates to form a singleunitof the said pieces.

f v 112. yA unitarybuilt-up structural steelsup- A.

means to 'adjust the transverse member'lon'- 'Y unit of the said pieces.

13. A unitary built-up structural steel support for a trolley base comprising a base plate cut from rolled steel and dished to give it stiffness and a pedestal member formed from rolled steel Vand projecting therefrom and Welded tothe base plate.

14. A unitary built-up structural steel support for a trolley base comprisingV a base plate cut from rolled steel plate and having associated therewith a pedestal member formed from rolled steel and projecting therefrom and Welded to the base plate.

15.' A unitary structural steel arm for a trolley base comprising a hinge member formed from rolled steel With a transverse opening for a pin, a drawn tubular member With a beveled inner surface to receive the end of a trolley pole welded to the hinge mem` ber and a larger drawn 'tubular member surrounding the lirst tubular member to" receive the trolley pole and Welded to the hinge member and means welded on the second tubular Y member to its ends.

16. A turret for a trolley basecomprising a tubular member to receive a support and having means to receive anti-friction bearings therein, arms projecting to receive springs for raising a trolley poleand a rubber bumperV positioned adj acent- "the turret and means secured to the turret to hold the bumper in place and means on the turret to pivotally receive an arm to support a trolley pole from grip the trolley pole intermediate the turret.

17. In a trolley base, the combination with a turret member of a support therefor comprising a plurality of structural steel members formed up and Welded together into a unitary structure, a pole arm comprising a plurality of structural steel members formed up and Welded together into a unitary structure, means to pivotally secure the arm tothe turret and spring means connected between the arm and turret biased to raise the free end of the arm.

18. In a trolley base, the combination With a turret member of a support therefor comprising a plurality of structural steel membersformed up and Welded together into a unitary structure, yielding means between the supportand turret to conduct current from the turret to the support, a pole arm comprising a plurality of structural steel members formed up and Welded together into a unitary structure, means to pivotally secure the arm to the turret and spring means connected between the arm and turret biased to raise the free end of the arm.

19. The method of building a trolley base comprising the steps of forming up a plate member of rolled sheet steel and providing a hole therein, forming a pedestal member of structural steel to receive a turret, forming a second smaller plate member With a hole therein and lthen assembling the plates with thepedestal Jrejecting therefrom through the coinciding holes, then Welding around the edge of the smaller plate to fuse and unite it to the larger plate and then fusing and Welding the edge of the pedestal to one of the plates, then providing a turret member to be supported by the pedestal with anti-friction bearings therebetween and having arms to receive springs and projecting means to receive a pole arm, then forming up of structural steelv a hollow arm with a structural steel reinforcing-member at one end, then forming a hinge member of structural steel to cooperate With the projecting means on theV turret vto pivotally support the arm and then Welding the hollow arm and the reinforcing member to the hinge, then forming a clamp member of structural steel with a second clamp member secured thereto by bolts and providing an opening in the first clamp member for an adjusting bolt, then fusing and Welding the shape to the end of the hollow arm, then forming of structural steel a member and vfurther forming of plate steel hoch-shaped members and Welding the hooked members to the ends of the last said member to receive springs also secured to the arms von the turret and providing a hole through the' said member to receive the said adjusting bolt.

20. The method of building a trolley base comprising the steps of forming up a plate member of rolled sheet steel and providing a hole therein, forming a pedestal member of structural steel to receive a turret and then assembling the plate with the pedestal proj ecting therefrom through the hole, then fusing and Welding the pedestal to the plate, then providing a turret member to be supported by the pedestal with anti-friction bearings therebetween and having arms to receive springs and projecting means to receive a pole arm, then forming from structural steel a hollow arm with a separately formed structural steel hinge member to cooperate with the projecting means on the turret to pivotally support the arm and Welding the hollow arm to the hinge, then forming a clamping member ofstructural steel with a second clamping member secured thereto and providing an opening in the irst clamping member Jfor anl throw of the arm and a spring vbiased to Vmove adjusting boltj' then Jfusing and welding` the the arm upwardly about Aits hinge.

shape to the hollow arm7V then forming ot structural steel a member and further formtures. lng of plate steel hook-shaped membersand welding thehooked members to the ends'of the last said member to receive springsalso securedto the arms on the turret and pror vidinga hole through'the saidl memberto receive the said adjusting bolt.

21. The method of forming Va trolley pole base consisting in forming a plurality l of parts from structural steel andwelding them f together to form a unitary support for a turret member, then forming a plurality of .parts from structural steel and weldingthem together to form a unitary pole-arm, then vpivotally mounting the pole-arm on the tur# ret andV then mounting the turret Aon the y support, then forming coiled springs and interposing them between the arm and turret to raise the free end of the arm.

22. In a trolley base7 the combination with a turret member, of a support therefor, a

.' pole-arm comprising a plurality of inembers formed from structural steel andwelded together into -a unitary structure, means to pivotally secure the arm to the turret and spring means connected between the arm and turret biased to y'raise lthe free end of the arm. A v v 23. In combination witha rotatable mem# berA having a pole-'armV secured thereto to pivot in a vertical plane and ksprings biasedV vto raise the freeend of the arm, of a fabri- Y cated support for the rotatable member comprisingV a plurality of parts formed of struc- 'tural steel and welded together. n Y

24. A support memberrfor a trolley base rcomprising a plurality of superimposed parts i and turret mounted thereon to rotate and a i pole-arm comprising a plurality of members (ITI formed from structural steel and welded Vtogether and pivotally secured to the turret,

spring means biased to move the free end ofA the arm upward and means on the turret cooperating with pivotal means 'formed up and welded tothe arm to hold the arm in a lowered position. v

27. A trolley base comprising a support, a pole arm supported by the said support and hinged to pivot in a Vertical plane and a deformable bumper of elastic material to be engaged by the arm to cushion the upward In testimony whereof we afx our signa- 

